And as you said, nelson mandela spent 27 years of his life in prison. We're going to look, now, at those years. What they were like for him and his family. And the kindness he received from someone you might not expect. One of his prison guards. When nelson mandela was sentenced to life in prison in 1964, he left behind his wife, winnie, and five children. Over the 27 years that followed, he held on to his connections with family through these letters. This particular notebook was for family correspondence. You will find letters to winnie. To his children. Reporter: Can you read a bit for us? I can. My darlings, a nice letter written reached me safely. And I was very glad to know that she is now. It pleases me very much to know that all of my children are doing well. I hope you will do even better at the end of the year. I was happy to learn that she can cook chips, rice, meats and other things. I'm looking forward to the day when I will be able to enjoy all that she cooks. And so on. Very moving stuff. Reporter: While he sat behind bars, there were deaths in the family. And new additions. Winnie tried to bring his newborn grandchild to robben island for him to meet for the first time. Can he see him from a distance. Reporter: While winnie waited, christo brand, a prison guard, snuck the baby to mandela. Brand developed a friendship with mandela during the years they spent at robben island. He helped teach mandela afrikaans, the language used by the white upper class. He used afrikaans to talk to his opposition. As mandela explained, if you talk to a man in a language he understands, that goes to his head. If you talk to him in his language, that goes to his heart. That's what he would drive for. That's what he was loved for. And that's why he fight for while he was in prison. To have people live in peace. Joining us now is human RIGHTS LAWYER, gay MacDougal, who worked closely with mandela after his release from prison. Just weeks after his release from prison in 1990, you were there with him. That must have been an incredible moment. I -- we were there for the independence elections of namibia. Quite an incredible event in and of itself. There he was, somebody that i had campaigned all my life to get released and never thought it would happen. And, gay, all that time, you were campaigning for him, he was in prison. But never thought of himself as anything but a free man and a leader. Absolutely. I think he always knew his place in history. And I think he always knew that he and his brother comrades in jail were going to be released someday and that apartheid would fall. He was refused to release many times. He did because he was not willing to be released on conditions. He was fighting for the whole pie, not just some little sliver of it. And he also didn't want to be separated from his comrades in the struggle. And he was very clear about that. Yes. He was very inclusive of making sure we were not singling out him. And we were just talking a moment ago. It had to have been an experience for you because you worked with him after. And the transition to democracy and the avalanche of change that you experienced. Well, it was. It was an avalanche of change. And it happened so much, it was overtaking us all day by day. But the greatest moment of my life was being able to stand next to him, when he voted for the first time. It was a moment when all the struggle and the suffering of his nation was soaked into that one moment of him dropping the ballot into the box. And it was a marvelous moment. 76 years old and voting for the first time. And his name was on the ballot. You were standing right next to him. It was unbelievable. And for me, it had great symbolism as an african-american woman. I was born and raised in the jim crow apartheid south of this country. I matured in the civil rights movement. Later, of course, I get to live through the election of the first african-american president of this country. So, you know, I felt in a sense that I was a bridge between the history of our two countries, which is very much there. I also felt like I was there symbolizing the international community and the importance of america and americans took a stand against apartheid. And said no to our government, when ronald reagan wanted to solidify, you know, our u.S. Support for apartheid. We said, no. And we played an important role in that. And that was very critical, as well. You did play an important role. It's a privilege to have you here today. Thank you.

This transcript has been automatically generated and may not be 100% accurate.

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